1. Field of the Invention
This invention relates to the assembly of large diameter, flanged pipe sections, and more particularly, to a flange alignment tool for facilitating alignment of the large, unwieldy pipe section flanges so that the bolt openings of the adjacent pipe section flanges come into precise alignment all around the abutting flanges to be bolted together.
2. Related Art
U.S. Pat. No. 3,878,597 shows a pneumatically powered tool for aligning holes in the flanges and angles of steel girders to be assembled to each other. The tool comprises jaw members held together by a split spring. The outer ends of the jaw members have pivotally attached tapered tips which are inserted through the bolt openings in adjacent girders. A wedge is hydraulically forced between the jaw members causing them to expand. This alignment tool does not provide uniform expansion in the adjacent bolt openings which is most important in aligning a pair of pipe flanges, both of which may move during the bolting procedure. It is important that the pipe flanges be precisely aligned to avoid leaking connections under pressure.
U.S. Pat. NO. 4,701,989 is directed to a pipe and flange alignment tool for properly assembling the flange on a pipe end so they can be welded together. This tool includes a plurality of spaced, radially extending pipe engaging means and flange engaging means disposed at opposite ends of the tool body. The pipe and flange engaging means are van-shaped members which extend through slits in the main body of the tool. This tool is apparently much larger in size than applicant's bolt alignment tool, and would be too complex to fit into the adjacent bolt openings of flanged pipe sections. If used as taught, it would require a long, manipulating handle for removal from the open end of adjacent pipe section after they are bolted together.